The present invention relates to firearms, and it relates more particularly to the type of firearm having a tubular magazine disposed within a fore-end grip beneath the barrel. Specifically, the invention relates to a detent device for preventing accidental loosening of the cap which covers the front end of the magazine tube.
In some types of shoulder arms, such as repeating shotguns which employ tubular magazines, the magazine is enclosed within a so-called fore-end grip, which is usually made of wood. It is common practice to form the grip so that it can be slipped longitudinally over the front end of the magazine and seated against the front end of the receiver or other portion of the gun. A cap is then threaded onto the end of the magazine tube projecting forward of the grip and tightened until it firmly engages an end surface of the grip and drives it rearward against the receiver, thereby holding the grip rigidly in place.
Likewise, in so-called pump-action guns a magazine cap may be provided which engages a bracket fixed to the barrel of the gun by which the front portion of the magazine is supported. In such arrangements the cap alone ordinarily holds the barrel in place instead of the fore-end grip, which in this case is slidably mounted for manually reloading and cocking the gun.
In these types of firearms, it is desirable to provide some means for preventing accidental loosening of the magazine cap while the gun is being used. To this end, a spring-loaded detent ball or plunger may be mounted either in the end surface of the grip for engagement with a ribbed or serrated surface on a peripheral portion of the cap, or in the case of pump-action guns, in the cap where it can engage a serrated surface on the magazine-mounting bracket.
The object of the present invention is to provide an improved detent for a magazine or fore-end cap in a tubular-magazine firearm, one purpose being to provide more positive action of the detent member than has been practical heretofore with conventional detents.